sync std.system and phobos.sys.system (#10871)

Author: kubo39

phobos/sys/system.d

@@ -1,4 +1,6 @@
 // Written in the D programming language.
+//
+// NOTE: This must be kept in sync with std/system.d
 
 /**
  * Information about the target operating system, environment, and CPU.
@@ -126,6 +128,9 @@ immutable
         sh, /// The SuperH architecture, 32-bit
         webAssembly, /// The WebAssembly virtual ISA (instruction set architecture), 32-bit
         alpha, /// The Alpha architecture
+        loongArch32, /// The LoongAtch architecture, 32-bit
+        loongArch64, /// The LoongArch architecture, 64-bit
+        xtensa, /// The Xtensa architecture, 32-bit
         unknown, /// Unknown
     }
 
@@ -156,5 +161,8 @@ immutable
     else version (SH)       ISA instructionSetArchitecture = ISA.sh;
     else version (WebAssembly) ISA instructionSetArchitecture = ISA.webAssembly;
     else version (Alpha)    ISA instructionSetArchitecture = ISA.alpha;
+    else version (LoongArch32) ISA instructionSetArchitecture = ISA.loongArch32;
+    else version (loongArch64) ISA instructionSetArchitecture = ISA.loongArch64;
+    else version (Xtensa)   ISA instructionSetArchitecture = ISA.xtensa;
     else ISA instructionSetArchitecture = ISA.unknown;
 }

std/system.d

@@ -1,4 +1,6 @@
 // Written in the D programming language.
+//
+// NOTE: This must be kept in sync with phobos/sys/system.d
 
 /**
  * Information about the target operating system, environment, and CPU.
@@ -39,6 +41,7 @@ immutable
         openBSD,   /// OpenBSD
         dragonFlyBSD, /// DragonFlyBSD
         solaris,   /// Solaris
+        haiku,     /// HaikuOS
         android,   /// Android
         otherPosix, /// Other Posix Systems
         unknown,   /// Unknown
@@ -58,7 +61,7 @@ immutable
     else version (OpenBSD) OS os = OS.openBSD;
     else version (DragonFlyBSD) OS os = OS.dragonFlyBSD;
     else version (Solaris) OS os = OS.solaris;
-    else version (Android) OS os = OS.android;
+    else version (Haiku) OS os = OS.haiku;
     else version (Posix)   OS os = OS.otherPosix;
     else OS os = OS.unknown;